Tri-Five Body Brace Repair

We get the final structural supports of our ’55 project’s body back to as-new condition.

Seeing this ’55 start coming together and becoming a solid car again has been nothing short of a magical experience for me. After playing in the car as a kid while it sat derelict in my parents’ garage and dreaming of one day actually driving it, every step that brings this car closer to hitting the street again is fairly euphoric. And I honestly enjoy being able to use the ’55 to share useful tips and techniques that can help you guys (and gals) get your own cars back on the road.

2/20

Thanks to Jim Barber and his crew at Classic Automotive Restoration Specialists in Belews Creek, North Carolina, our last installment (Chevy Classics, 2011 issue) saw us dealing with the cowl ears/shoulders and getting them back into shape along with the areas inside the cowl exposed to moisture and that had rusted out. Because the ’55 (and her Tri-Five siblings) predate the use of galvanized steel in body construction (mid-to-late ‘60s) pretty much any unprotected steel area that can collect water will rust.

On our car, the rockers suffered from extensive rot, especially the passenger side, which had most of its bottom completely rusted out. Not content to just eat the rocker, the corrosion spread to some of the body braces/mounts, necessitating their replacement. Because the floor braces also act as body mounts, having these parts weakened by rust also compromises the car’s structural integrity and connection the chassis.

The good news though is repairing these braces isn’t that hard, and our friends at Danchuk offer all the necessary replacement pieces to handle the job. Making things even easier, Danchuk also offers the end sections of the center and front floor braces, so you don’t have to remove the whole piece and replace it if just the end sections next to the rockers are rusted out. Another beautiful thing about the Tri-Five design was that all three years used the same body braces spread across the different models (hardtop, sedan, sport sedan, four door sedan, wagon, etc.) so it doesn’t matter what year your car is, Danchuk’s got the parts.

Since our car had several braces with issues, we raided the Danchuk catalog and got the parts necessary to replace them all. We’re just focusing on one brace in this story, but the installation is pretty much the same for all of them. The equipment used is simple and straightforward: 110-volt MIG welder, drill, hammer, and chisel—stuff any guy can have in his garage.

Sources

MORE PHOTOS

VIEW FULL GALLERY

xclose

Tri-Five Body Brace Repair

18 Here she is, all set except for the welds to the inner rocker, which we’ll take place once we’ve double checked all the alignments to make sure the inner and outer rockers are in position. We’ll also go back and clean up/smooth the welds, so once the underside’s painted you’ll never see them.

1. First up is to clean up the area around the brace and expose the factory spot welds. An abrasive or cleanup disc is all that’s needed.

2. All it takes is a standard spot weld drill bit to take care of the old factory welds. A heavy duty electric or air drill does make the process easier.

3. Since it’s easy for things to get out of control with an air chisel, and we don’t want to damage our floors, which are in good shape, Brandon Grimes at CARS went with the old fashioned hammer method to split the brace from the floor.

4. Taking a break to rest his arms, Brandon went ahead and scuffed the back-side of the new brace, then painted it with some weld through zinc primer. By the time we get the old brace out, this will be dry and ready for installation.

5. The top rocker side of the brace where it curved with the floor needed a little persuasion from the cutoff wheel to help free it up.

6. Once that was done, Brandon used a heavy pry bar and gentle, but constant leverage to break the old brace free from the floor. If your floors are in good shape and you don’t want to mangle them, patience and finesse are the best things to use when prying the old mounts/braces free.

7. The chisel had to be used again in the tricky corner to finish freeing things up.

8. Finally the brace popped free. It’s done a good job for 56-plus years, but it’s time for retirement and new steel to take its place.

9. Here’s the new (right) next to the old. Corrosion has taken its toll on the old one, and you can see where the drain hole at the dog leg has rusted through and the cancer spread outward.

10. Before the new brace could be installed, the now exposed floor area needs to be cleaned up and treated to prevent rust from returning.

11. Again, the sanding disc goes to work, getting rid of the scale and crud. Like with our other rust repairs, prep and cleaning work is crucial at this stage to prevent future corrosion problems. If you’re not sure about something, err on the side of caution. Clean the metal, then primer/treat it for rust protection.

12. The area cleaned off was painted with weld through zinc primer. Not only does the zinc primer protect the surface from rust, but it maintains the conductivity of the metal so you can weld without issues.

13. Since the new brace will be plug welded to the floor, holes need to be punched in the brace’s flange.

14. Test fitting the new piece, it slips right in place, so everything’s good to go …

15. … except for one little thing. We had a piece of metal left over from the old brace still stuck to the floor. A little work with the chisel and the offending remnant was gone ...

16. … leaving just a little work with the body hammer to smooth things out.

17. Using a 110-volt MIG welder, Brandon plug welds the brace to the floor. One thing to watch out for when using zinc primer is it tends to throw a lot of sparks. Make sure the area you’re welding in is clean of burnable grease and oils, along with the area around your car.

18. Here she is, all set except for the welds to the inner rocker, which we’ll take place once we’ve double checked all the alignments to make sure the inner and outer rockers are in position. We’ll also go back and clean up/smooth the welds, so once the underside’s painted you’ll never see them.

COMMENTS

related articles

Were back with our 1955 Chevy Tri-Five and were tackling the rust damage from the body. With replacement parts from Danchuk with go through all the damage and bring our '55 up to standard. Only at www.superchevy.com, the official website for Super Chevy Magazine. » Read More

We take a look at the top chassis's and performance suspension parts for Tri-Five Chevy's in out annual Chevy Classics Suspension Buyers Guide. Only at www.superchevy.com, the official website for Super Chevy Magazine. » Read More

Check out all the production data sheets for all Tri-Five Chevy's built from 1955-1957. We include the model year data, engine and transmission availability, the options and accessories and even the original paint colors. Only at www.superchevy.com, the official website for Super Chevy Magazine. » Read More